Synchronous rectification has become a preferred approach of achieving higher efficiency switching power supplies, especially in step-down industrial applications. Additionally, a present requirement dictates that power supplies be capable of starting into a pre-bias load condition where the initial load voltage has a value that is non-zero. This may be generally referred to as a power converter having the capability to monotonically start-up into pre-biased loads. Synchronous rectifiers are capable of conducting output current in both directions thereby allowing sinking and sourcing of the output current. If not controlled, the reverse (sinking) current flow can interfere with normal start-up of a DC-DC converter or even cause damage to the unit. Improvements to prevent sinking of an output current, especially during converter start-up, would prove beneficial to the art.